Unfortunately I don't have XRF capability in house. I'm hoping to get approval to send it out. Interesting theory Steve. The only thing about that theory that I don't understand is why it would be in the same location on two boards, but not on the rest. It's possible that it was just luck, but it isn't a super satisfying answer. I'll see what analysis I can get approved and if it supports that theory. Thank you! Tom On Thu, Feb 7, 2019 at 7:51 AM Steve Herring <[log in to unmask]> wrote: > Is it possible there was a glass fiber on that area when it was plated, > leaving you with the original copper foil thickness? > The fiber was then removed prior to ENIG? > > My guess at the cause. > > Steven E Herring > Director of Engineering > Pennatronics Corp > > -----Original Message----- > From: TechNet [mailto:[log in to unmask]] On Behalf Of FTL Quality > Sent: Thursday, February 07, 2019 3:07 AM > To: [log in to unmask] > Subject: Re: [TN] "Wrinkle" on outer copper layer > > Are you able to complete an XRF analysis on the Nickel thickness of the > ENIG? > > -----Original Message----- > From: Tom Brendlinger > Sent: Wednesday, February 6, 2019 8:36 PM > To: [log in to unmask] > Subject: [TN] "Wrinkle" on outer copper layer > > Hello TechNet, > > I've recently received some boards that have a defect I've never seen > before. > > There is a linear depression in a 2oz outer copper layer on two out of 45 > boards. One of the boards was on a solder sample panel, the other was > assembled with the defect. > > The depression has the appearance of a wrinkle or groove, it is > approximately straight and square to the edge of the board. At its widest > point it is about 0.006" wide, and as far as we can measure it is between > 0.0015" and 0.002" deep. There are a couple of small delaminations nearby > (on a panel that has not been reflowed). > > I looked through IPC-A-600 and did not find anything about this type of > issue. I don't have the equipment to microsection or x-ray the board, so > I'm not sure whether the foil is damaged under the plating (Which is RoHS > ENIG). > > Hopefully this image link works: > https://snag.gy/Kx58Oy.jpg > > Please let me know if you've seen this before or otherwise know how I can > find more information. > > Thank you! > Tom Brendlinger > Senior Electrical Engineer > Superpedestrian, Inc. >